The Feedback option enables you to
control whether user experience information is sent to Microsoft. The
information that is collected is used to improve Windows Phone. If you
choose to enable the Feedback feature, feedback information is sent
only over Wi-Fi connections; your cellular connection is never used. To
configure feedback, go to the Settings screen and perform the following
steps:

1. Tap Feedback.

2. Use the slide bar to turn feedback either on or off.

Protecting Your Privacy

Because your phone likely contains a
lot of personal information, it is important to take steps to protect
your privacy. As such, I recommend that you read Microsoft’s privacy
statement before enabling the Feedback feature. It is also worth noting
that feedback information is sent only over a Wi-Fi connection. Even
so, you should be aware that the phone might send as much as 10MB of
feedback data every seven days.